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1.
Glob Chang Biol ; 30(1): e17049, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37988188

RESUMO

Nanoparticle pollution has been shown to affect various organisms. However, the effects of nanoparticles on species interactions, and the role of species traits, such as body size, in modulating these effects, are not well-understood. We addressed this issue using competing freshwater phytoplankton species exposed to copper oxide nanoparticles. Increasing nanoparticle concentration resulted in decreased phytoplankton species growth rates and community productivity (both abundance and biomass). Importantly, we consistently found that nanoparticles had greater negative effects on species with smaller cell sizes, such that nanoparticle pollution weakened the competitive dominance of smaller species and promoted species diversity. Moreover, nanoparticles reduced the growth rate differences and competitive ability differences of competing species, while having little effect on species niche differences. Consequently, nanoparticle pollution reduced the selection effect on phytoplankton community abundance, but increased the selection effect on community biomass. Our results suggest cell size as a key functional trait to consider when predicting phytoplankton community structure and ecosystem functioning in the face of increasing nanopollution.


Assuntos
Ecossistema , Fitoplâncton , Biodiversidade , Biomassa , Água Doce
2.
Dis Markers ; 2022: 5772089, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692887

RESUMO

Previous studies have suggested an association of the expression of activating transcription factor-2 (ATF-2) with the survival time and the activity of the Wnt/Ca2+ signaling pathway in non-small-cell lung cancer (NSCLC). However, the exact role of ATF-2 in tumorigenesis and its underlying mechanism remains unclear. In this study, we study whether ATF-2 regulates the growth and reproduction of NSCLC cells through the Wnt/Ca2+ pathway. The expression of ATF-2 and pathway-related genes in non-small-cell lung cancer was detected by qRT-PCR and Western blotting. CRISPR/Cas9 technology was used to knock out the ATF-2 gene, and pathway inhibitors and agonists were added to induce cultured cells. The expression of pathway genes and the proliferation and invasion ability of A549 lung cancer cells were analyzed. ATF-2 and pathway-related genes were upregulated in NSCLC. The proliferation and invasion ability of A549 lung cancer cells was decreased after only adding pathway inhibitors. The expression of Wnt/Ca2+ pathway protein was decreased when the ATF-2 gene was knocked out, but the expression of Wnt/Ca2+ pathway protein was reversed after the addition of a pathway agonist. These results suggest that ATF-2 acts as an agonist in the Wnt/Ca2+ signaling pathway, promoting the expression of Wnt5a, Wnt11, CaMK II, and NLK in the Wnt/Ca2+ pathway, thereby regulating the proliferation and invasion of NSCLC cells.


Assuntos
Fator 2 Ativador da Transcrição/metabolismo , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Sinalização do Cálcio , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteínas Serina-Treonina Quinases , Via de Sinalização Wnt/genética
3.
J Cell Mol Med ; 25(19): 9168-9182, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34510715

RESUMO

Existing literature has highlighted the tumour suppressive capacity of microRNA-15a (miR-15a); however, its role in hepatocellular carcinoma (HCC) remains relatively unknown. This study aimed to investigate the role of miR-15a in HCC and the associated underlying mechanism. Initially, RT-qPCR was performed to detect the expression of miR-15a in HCC tissues and cells. Bioinformatics analysis, Pearson correlation coefficient, dual-luciferase reporter assay, and molecular approaches were all conducted to ascertain the interaction between miR-15a and O-linked N-acetylglucosamine (GlcNAc) transferase (OGT). PUGNAc treatment and cycloheximide (CHX) assay were performed to evaluate O-GlcNAc and the stabilization of the enhancer of zeste homolog 2 (EZH2). Finally, gain- and loss-of-function studies were employed to elucidate the role of P53 and the miR-15a/OGT/EZH2 axis in the progression of HCC, followed by in vivo experiments based on tumour-bearing nude mice. Our results demonstrated that the miR-15a expression was decreased in the HCC tissues and cells. P53 upregulated miR-15a expression, which inhibited the proliferation, migration and invasion of HCC cells, while inducing apoptosis and triggering a G0/G1 cell cycle phase arrest. OGT stabilized EZH2 via catalysing O-GlcNAc, which reversed the effect of P53 and miR-15a. The results of our in vivo study provided evidence demonstrating that P53 could suppress the development of HCC via the miR-15a/OGT/EZH2 axis. P53 was found to inhibit the OGT expression by promoting the expression of miR-15a, which destabilized EZH2 and suppressed the development of HCC. The key findings of our study highlight a promising novel therapeutic strategy for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , N-Acetilglucosaminiltransferases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Biomarcadores Tumorais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Perfilação da Expressão Gênica , Xenoenxertos , Humanos , Camundongos , Prognóstico
4.
Cancer Gene Ther ; 28(5): 486-501, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33277615

RESUMO

Recent studies have illustrated the role of aberrant regulatory interactions in the mediation of malignant phenotypes of cancer cells, which could potentially provide novel therapeutic targets to limit the destructive recurrence and metastasis of hepatocellular carcinoma (HCC). Herein, we clarify the oncogenic role of the long noncoding RNA (lncRNA) distal-less homeobox 6 antisense 1 (DLX6-AS1) in HCC in vivo and in vitro. To this end, we knocked down lncRNA DLX6-AS1 and manipulated the expression of miR-513c to characterize their effects in HCC cell viability, migration, invasion, and apoptosis. Furthermore, we probed the interactions with miR-513c's target gene Cullin4A (Cul4A) and the degradation of Annexin A10 (ANXA10) protein. Our data show that lncRNA DLX6-AS1 and Cul4A were highly expressed, while miR-513c and ANXA10 were poorly expressed in HCC tissues and cells. Moreover, the silencing of lncRNA DLX6-AS1 impeded the viability, invasion, and migration of HCC cells, while stimulating cell apoptosis. Further data indicated that lncRNA DLX6-AS1 targeted and repressed miR-513c expression, where the tumor-inhibiting effects of lncRNA DLX6-AS1 silencing was achieved by elevating miR-513c expression. Importantly, the lncRNA DLX6-AS1 upregulated the expression of Cul4A through sponging of miR-513c. The silencing of Cul4A restricted the malignant phenotypes of HCC cells by repressing the ubiquitination-mediated degradation of ANXA10. In vivo experiments verified that lncRNA DLX6-AS1 promoted the progression of HCC through the miR-513c/Cul4A/ANXA10 axis. Thus, the silencing of lncRNA DLX6-AS1 impaired miR-513c-dependent Cul4A inhibition and subsequently elevated ubiquitination-mediated degradation of ANXA10, thereby preventing the occurrence and development of HCC.


Assuntos
Anexinas/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas Culina/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Animais , Anexinas/genética , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Proteínas Culina/genética , Feminino , Proteínas de Homeodomínio/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , RNA Antissenso/genética , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Am J Transl Res ; 11(7): 4552-4560, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396359

RESUMO

Non-coding RNAs (ncRNAs) have been demonstrated to modulate the oncogenesis of non-small cell lung cancer (NSCLC), especially the long non-coding RNAs (lncRNAs). However, the role of lncRNA FOXC2-AS1 in the NSCLC is still unclear. In this research, we find that lncRNA FOXC2-AS1 is involved to NSCLC oncogenesis. The ectopic high-expression level of FOXC2-AS1 is closely correlated with the limited NSCLC patients' survival. In the functional experiments, the knockdown of FOXC2-AS1 dramatically suppressed the NSCLC cells' (A549, H460) proliferation, accelerated the apoptosis and induced the cycle arrest at G0/G1 phase. Mechanistic experiments revealed that FOXC2-AS1 repressed the p15 expression via recruiting the polycomb repressive complex 2 (PRC2) to the promoter of p15. The interaction within FOXC2-AS1 and p15 was validated using the rescue experiments. In conclusion, the results in this work confirmed that FOXC2-AS1 could aggravate NSCLC oncogenesis through repressing p15 expression via interacting EZH2, which provide new idea for the NSCLC therapeutic strategy.

6.
Inorg Chem ; 57(5): 2766-2772, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29470062

RESUMO

Oxygen evolution reaction (OER), as the critical step in splitting water, is a thermodynamically "up-hill" process and requires highly efficient catalysts to run. Arrhenius' law suggests that the higher temperature, the faster the reaction rate, so that a larger OER current density can be achieved at a lower η. Herein, we report an abnormal temperature effect on the performance of Co-based catalysts, e.g., Co3O4, Li2CoSiO4, and Fe-doped Co(OH) x, in OER in alkaline electrolytes. The OER performance reached a maximum when the temperature increased to 65 °C, and the OER performance declined when the temperature became higher. The mechanism was investigated by using Co3O4 as a model sample, and we propose that at an optimal temperature (around 55-65 °C) the main rate-determining step changes from OH- adsorption dominant to a mixed mode and both the adsorption and the cleavage of the OH group can be rate-determining, which leads to the fastest kinetics.

7.
Nanoscale ; 10(1): 386-395, 2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29218342

RESUMO

Functional porous carbon materials are widely used to solve the low conductivity and shuttle effect of Li-S batteries; however, the common carbon/sulfur composite electrodes based on traditional technology (with conducting agents and binders) make it difficult for a battery to work stably at an ultra-high sulfur loading of 10 mg cm-2. Herein, an appropriate content of sulfur was injected into a pomegranate-like structure self-assembled with nanohollows (PSSN) of N-graphene. The Li-PSSN/S battery based on traditional technology displays a large-capacity, high-rate and long-life at an ultra-high areal-sulfur loading of 10.1 mg cm-2. The excellent performance with ultra-high areal-sulfur loading can be attributed to the hierarchal nanohollows with graphene-shells being in close contact to build a 3D-electronic conduction network and promoting electrolyte adsorption into the entire electrode to maintain rapid Li-ion transport, while stopping the shuttle-effect via the strong interaction of polysulfide with the doped N elements on graphene-shells. In addition, the exact sulfur content can provide just enough space to maintain the huge volume change and constant thickness of the S-electrodes during the charge-discharge process to enhance the cycling stability.

8.
ACS Appl Mater Interfaces ; 9(19): 16159-16167, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28447457

RESUMO

Co3O4-δ quantum dots (Co3O4-δ-QDs) with a crystallite size of approximately 2 nm and oxygen vacancies were fabricated through multicycle lithiation/delithiation of mesoporous Co3O4 nanosheets. Used as an oxygen evolution reaction (OER) electrocatalyst for water splitting, the catalytic performance (an overpotential of 270 mV@10 mA cm-2 and no decay within 30 h) of Co3O4-δ-QDs is superior to that of previously reported Co-based catalysts and the state-of-the-art IrO2. Compared to that of the Co3O4 nanosheets, the enhanced OER activity of Co3O4-δ-QDs is attributed to two factors: one is the increased quantity of the Faradaic active sites, including the total active sites (q*Total), the most accessible active sites (q*Outer), and their ratio (q*Outer/q*Total); the other is the enhanced intrinsic electroactivity per active site evaluated by the turnover frequency and the current density normalized by the most accessible active sites (j/q*Outer) related to the OER. This multicycle lithiation/delithiation method can be applied to other transition metal oxides as well, offering a general approach to develop high-performance electrocatalysts for water splitting.

9.
Eur J Pharm Biopharm ; 115: 177-185, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28263795

RESUMO

Poly (lactide-co-glycolide) (PLGA) microparticles are widely used for controlled drug delivery. Emulsion methods have been commonly used for preparation of PLGA microparticles, but they usually result in low loading capacity, especially for drugs with poor solubility in organic solvents. In the present study, the nanocrystal technology and a water-soluble polymer template method were used to fabricate nanocrystal-loaded microparticles with improved drug loading and encapsulation efficiency for prolonged delivery of breviscapine. Breviscapine nanocrystals were prepared using a precipitation-ultrasonication method and further loaded into PLGA microparticles by casting in a mold from a water-soluble polymer. The obtained disc-like particles were then characterized and compared with the spherical particles prepared by an emulsion-solvent evaporation method. X-ray powder diffraction (XRPD) and confocal laser scanning microscopy (CLSM) analysis confirmed a highly-dispersed state of breviscapine inside the microparticles. The drug form, loading percentage and fabrication techniques significantly affected the loading capacity and efficiency of breviscapine in PLGA microparticles, and their release performance as well. Drug loading was increased from 2.4% up to 15.3% when both nanocrystal and template methods were applied, and encapsulation efficiency increased from 48.5% to 91.9%. But loading efficiency was reduced as the drug loading was increased. All microparticles showed an initial burst release, and then a slow release period of 28days followed by an erosion-accelerated release phase, which provides a sustained delivery of breviscapine over a month. A relatively stable serum drug level for more than 30days was observed after intramuscular injection of microparticles in rats. Therefore, PLGA microparticles loaded with nanocrystals of poorly soluble drugs provided a promising approach for long-term therapeutic products characterized with preferable in vitro and in vivo performance.


Assuntos
Flavonoides/química , Ácido Láctico/química , Ácido Poliglicólico/química , Polímeros/química , Água/química , Animais , Disponibilidade Biológica , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Feminino , Microesferas , Nanopartículas/química , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Solubilidade , Solventes/química
10.
Drug Deliv ; 23(9): 3674-3680, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27689622

RESUMO

Lung-targeting sophoridine-loaded poly(lactide-co-glycolide) (PLGA) microspheres were constructed by a simple oil-in-oil emulsion-solvent evaporation method. The obtained microspheres were systematically studied on their morphology, size distribution, drug loading, encapsulation efficiency, in vitro release profile, and biodistribution in rats. The drug-loaded microparticles showed as tiny spheres under SEM and had an average size of 17 µm with 90% of the microspheres ranging from 12 to 24 µm. The drug loading and encapsulation efficiency were 65% and 6.5%, respectively. The in vitro drug release behavior of microspheres exhibited an initial burst of 16.6% at 4 h and a sustained-release period of 14 days. Drug concentration in lung tissue of rats was 220.10 µg/g for microspheres and 6.77 µg/g for solution after intraveneous injection for 30 min, respectively. And the microsphere formulation showed a significantly higher drug level in lung tissue than in other major organs and blood samples for 12 days. These results demonstrated that the obtained PLGA microspheres could potentially improve the treatment efficacy of sophoridine against lung cancer.


Assuntos
Alcaloides/administração & dosagem , Alcaloides/química , Ácido Láctico/química , Neoplasias Pulmonares/tratamento farmacológico , Ácido Poliglicólico/química , Quinolizinas/administração & dosagem , Quinolizinas/química , Animais , Química Farmacêutica/métodos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Portadores de Fármacos/química , Emulsões/administração & dosagem , Emulsões/química , Pulmão/efeitos dos fármacos , Masculino , Microesferas , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Solventes/química , Distribuição Tecidual , Matrinas
11.
J Diabetes Res ; 2016: 7913258, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27563680

RESUMO

Native Hawaiians and other Pacific Islanders (NH/PI; e.g., Samoan and Chuukese) have higher type 2 diabetes prevalence compared to other groups in Hawai'i. Partners in Care (PIC), a culturally tailored, community-based, diabetes self-management education intervention (DSME), is effective at improving participants' glycemic control and self-care behaviors. Maintenance of improvements is challenging. Diabetes-related social support groups (SSG) are a promising maintenance component for DSME. This study examined the effects of a diabetes-specific SSG component relative to a control group, after the receipt of the 3-month PIC intervention, which was delivered to 47 adult NH/PI with type 2 diabetes. Participants were then randomized to either a 3-month, 6-session SSG or a control group. Hemoglobin A1c (HbA1c), blood pressure, triglycerides, cholesterol, and diabetes self-management knowledge and behaviors were assessed at baseline, 3 months, and 6 months. Results indicated significant improvements in HbA1c, diabetes-related self-management knowledge, and behaviors from baseline to 3-month assessment. However, no differences between the SSG and control group from 3-month to 6-month assessment suggest that all participants were able to maintain initial improvements. The SSG group had a significant decrease in systolic blood pressure from 3-month to 6-month assessment while the control group did not. Study limitations and future directions are discussed.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Conhecimentos, Atitudes e Prática em Saúde , Havaiano Nativo ou Outro Ilhéu do Pacífico , Grupos de Autoajuda , Apoio Social , Adulto , Idoso , Glicemia/metabolismo , Pressão Sanguínea , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/psicologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Autocuidado , Estresse Psicológico/psicologia , Triglicerídeos/metabolismo
12.
Transl Behav Med ; 6(2): 190-201, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27356989

RESUMO

A previously translated Diabetes Prevention Program Lifestyle Intervention (DPP-LI) was adapted for delivery as a worksite-based intervention, called PILI@Work, to address obesity disparities in Native Hawaiians/Pacific Islanders. This study examined the effectiveness of PILI@Work and factors associated with weight loss at post-intervention. Overweight/obese employees of 15 Native Hawaiian-serving organizations received the 3-month component of PILI@Work. Assessments included weight, systolic/diastolic blood pressure, physical activity and functioning, fat intake, locus of weight control, social support, and self-efficacy. Weight, systolic/diastolic blood pressure, physical functioning, physical activity frequency, fat intake, family support, and eating self-efficacy improved from pre- to post-intervention. Regression analysis indicated that worksite type, decreased diastolic blood pressure, increased physical activity, and more internalized locus of weight control were significantly associated with 3-month weight loss. PILI@Work initiated weight loss in Native Hawaiians/Pacific Islanders. DPP-LI translated to worksite settings and tailored for specific populations can be effective for addressing obesity.


Assuntos
Agentes Comunitários de Saúde/organização & administração , Diabetes Mellitus/prevenção & controle , Promoção da Saúde/métodos , Obesidade/prevenção & controle , Programas de Redução de Peso/organização & administração , Adulto , Diabetes Mellitus/etnologia , Feminino , Havaí , Educação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico , Obesidade/etnologia , Serviços de Saúde do Trabalhador/organização & administração , Avaliação de Programas e Projetos de Saúde , Análise de Regressão , Comportamento de Redução do Risco
13.
Int J Pharm ; 496(2): 723-31, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26581771

RESUMO

The O/W emulsion method has been widely used for the production of poly (lactide-co-glycolide) (PLGA) microparticles. Recently, a template method has been used to make homogeneous microparticles with predefined size and shape, and shown to be useful in encapsulating different types of active compounds. However, differences between the template method and emulsion method have not been examined. In the current study, PLGA microparticles were prepared by the two methods using glycyrrhetinic acid (GA) as a model drug. The properties of obtained microparticles were characterized and compared on drug distribution, in vitro release, and degradation. An encapsulation efficiency of over 70% and a mean particle size of about 40µm were found for both methods. DSC thermograms and XRPD diffractograms indicated that GA was highly dispersed or in the amorphous state in the matrix of microparticles. The emulsion method produced microparticles of a broad size distribution with a core-shell type structure and many drug-rich domains inside each microparticle. Its drug release and matrix degradation was slow before Day 50 and then accelerated. In contrast, the template method formed microparticles with narrow size distribution and drug distribution without apparent drug-rich domains. The template microparticles with a loading efficiency of 85% exhibited a zero-order release profile for 3 months after the initial burst release of 26.7%, and a steady surface erosion process as well. The same microparticles made by two different methods showed two distinguished drug release profiles. The two different methods can be supplementary with each other in optimization of drug formulation for achieving predetermined drug release patterns.


Assuntos
Emulsões/síntese química , Ácido Glicirretínico/síntese química , Ácido Láctico/síntese química , Microesferas , Ácido Poliglicólico/síntese química , Química Farmacêutica , Emulsões/farmacocinética , Ácido Glicirretínico/farmacocinética , Ácido Láctico/farmacocinética , Tamanho da Partícula , Ácido Poliglicólico/farmacocinética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Difração de Raios X
14.
Ying Yong Sheng Tai Xue Bao ; 21(12): 3120-6, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21442998

RESUMO

Through the human-computer interactive interpretation of the 2000, 2005, and 2008 remote sensing images of Zhejiang Province with the help of RS and GIS techniques, the dynamic database of cultivated land change in the province in, 2000-2008 was established, and the driving factors of the cultivated land change were analyzed by ridge regression analysis. There was a notable cultivated land change in the province in 2000-2008. In 2000-2005 and 2005-2008, the annual cultivated land change in the province arrived -1.42% and -1.46%, respectively, and most of the cultivated land was changed into residential and industrial land. Non-agricultural population rate, real estate investment, urban green area, and orchard area were thought to be the main driving factors of the cultivated land change in Zhejiang Province, and even, in the developed areas of east China.


Assuntos
Agricultura/tendências , Produtos Agrícolas/crescimento & desenvolvimento , Indústrias/tendências , Agricultura/economia , China , Sistemas de Informação Geográfica , Comunicações Via Satélite , Fatores Socioeconômicos , Solo/análise
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